Kohler Rialto K-3402 toilet fill valve repair

I found the forum doing some research on my cranky Kohler 3402PB. Couple of questions if you don't mind.

I can't seem to find much reference to the 3402PB model, only the 3402. Is it normally just referred to as the 3402, or do I have some other variant?

I am rather shocked to find that Kohler is almost entirely unavailable as an aftermarket parts pruchase. It would appear that the rubber plunger inside the fill valve has deteriorated, and is causing a faint but perceptible continuous fill noise. Is it possible to find this plunger by itself, or am I really stuck paying $80-90 for a whole new assembly.

If not, I'm seriously considering taking a shot at replacing the entire toilet with a new one. Appears to be rather straightforward as a one piece unit. For someone only moderately mechanically inclined, any tips.

"Our Kohler Rialto (~12 yrs old K3402) started running about 2 years ago but could be stopped (until about 5 months ago) by tightening the top center screw of the ballcock to push down the plunger to stop the water flow. I saw online that Kohler no longer made the ballcock (refill valve) and I would have to buy a new toilet. A local plumbing supply house had them but they cost ~$98!!! Further online research has finally shown that this Kohler ballcock valve is Model 1B1-X made by Coast Foundries for Kohler. The top cap on ours says "Kohler Co. 1B1-X Sheath Ballcock". I found new 1B1-X ballcocks (~$24)and rebuild kits ($3.69) online at Ace hardware and DoItBest hardware stores. The new 1B1-X ballcocks don't have the lower flush float valve that feeds the rim flush so I purchased the rebuild kit at a local DoItBest hardware store (part number 450758 O/M 1-25) and repaired our old one in about 10 minutes. (Wouldn't it be nice if Kohler told us that a couple of years ago instead of telling us we needed to buy a new toilet)." S. McMillan

The new 1B1-X ballcocks don't have the lower flush float valve that feeds the rim flush so I purchased the rebuild kit at a local DoItBest hardware store (part number 450758 O/M 1-25) and repaired our old one in about 10 minutes.

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I've been struggling with another cranky Rialto style K-3397 and thinking a replacement of the 1B1X would be the next step. And I don't feel like spending $97.50 on a Kohler rebuild kit. I think I need to replace the flap as well.

Will I need to find the rebuild kit with the lower flush float valve for the K-3397 as well?

Their worth ranges from whatever you can get for them, to whatever you have to pay to have someone take them away. But why would you want to. That toilet will not overflow if it gets plugged up, (and they do not make any new ones with that feature), which makes it ideal for a second floor bathroom. A new flapper and a 1B-1X fill valve makes them as good as new. The 1B-1X does not need the lower float. It uses a diversion valve to send a portion of the flow to the rim to assist with the flush. You cut the original plastic rim hose off and insert the smaller one from the 1B-1X into it.

Sorry to piggyback on this thread but it looks like a similar post and I need the photo of the fill valve in there.

Kindly help. I am almost at wit's end!

It's now been almost 2 weeks (a blown angle stop, soaking bathroom carpet and padding, 3 plumbers visits, etc) and I cannot recall exactly the problem with my toilet. For one thing, the old fill valve was spraying random jets of water out its side, getting too close to the mysterious four holes in the back of the toilet tank (which Kohler says were probably for hanging the toilets on the assembly line but just could be for some sort of vacuum/veniliation, so maybe I shouldn't block them!). I also think it had a slow leak, possibly due to a very worn flapper. The plumber took one look at the old valve and immediately decided to replace it with a PF140999 one piece ballcock by PROFLO (also replaced the flapper, which was very worn). This valve looks exactly like the photo HJ posted in this thread. Becasue I have a second such toilet upstairs with the original valve, I can see that this replacement valve is missing a swivel thingee on the side of the valve. Also, the outlet that connects to the front of the tank (for rim wash, I think) is positioned about 1.5 inches higher than on the original valve, therefore causing that line to be barely uphill whereas on the original, it is quite a bit more of an incline. Also, on the old toilet, it looks like the outlet on the fill valve for the rim feed fits right into the toilet tank's 6" curved, run of very hard plastic that runs all the way to the front of the tank; whereas with the new valve, it looks like this plumber may have cut out most of the hard plastic run and instead inserted about 6 inches of flex clear plastic hose that came with the new valve, inserting one end over the valve outlet and the other end into the only one inch of the hard plastic run. The difference being that water can conceivably leak into the hard plastic at a much higher height in the badly performing toilet than it can on the old unit (on the old unit, it can enter right at the low height of the outlet of the fill valve, but then has a much steeper uphill run).

The reason I mention all this is that, with this new fill valve (1 B1-X, which says it fits 7 brands of 1 piece toilets), I cannot get the fill valve to shut off 100%. There is always some hissing and, sometimes, almost randomly, 15 minutes later the quiet hissing slowly builds up and turns noisy (almost like the sound of a siphon pressure building up as it reaches full volume). At this point, I notice that the tank water level has dropped about 1/4 inch, where it stays, until I flush again. I notice that bubbles of water also can then be seen going through that clear tube feeding the rim of the bowl. And drops of water fall from the flex clear hose just where it enters the hard plastic run sometimes. It seems that some sort of odd siphoning action is happening here.

It is driving me nuts. So any of these clues above suggest why this is happening? The plumber, after 3 visits, has written it off as finicky and has lost interest, particularly in waiting for 15 minutes each time he adjusts to see if the noise goes away (he, apaprently, correctly tells me Kohler is still looking for a new supplier for what will apparently be a conversion kit, possibly becasue they know this system stinks and they expect it to cost over $100 when they finally find a manufacturer).

Manually lifting the rod always eliminates any noise so I assume that somehow or another, if the water level is dropping, the valve cannot cause the water level in the tank to refill high enough to shutoff the valve - the water must be leaking off into the bowl, or down the drain, I assume. The doughnut below the FLUSH valve may have a tiny, tiny slow leak. I have turned every screw, bent the lever arm, and nothing seems to work for more than 2 or 3 flushes in a row.

With some further research, I find that my ProFlo after market fill valve is a private label for Ferguson Plumbing, coordinated by a firm called Lincoln Products. They tell me the 1 B1-X, despite the label Ferguson insists upon, is actually misssing a secondary float that is on the original Kohler valve and, indeed, I now see that is true. Apparently, that secondary float assembly and output for the rim wash will mount to the 1 B1-X in place of the current elbow and output (for rim wash) and that my plumber should have known to take the old secondary float and put it there. He apparently trashed it and dind't notice the difference in the new valve. In the plumber's defesne, the Ferguson packaging says nothing to indcate an additionaly piece is required for certain Kohler toilets. TheLincoln products guy says that Kohler does not allow anyone esle to make that secondary float and so it is not available and that the fill valve won't work without it. Kohler tech support says I don't really need the secondary float and, in fact, they often tell customers to get rid of it! They suggest that the plastic pipe going from the back of the tank to the bowl is not really a sealed entry and so it is necessary to make sure the water level is below where that pipe meets the china. It seems that the louder back siphoning noise is more of a problem when I set the tank water level lower, so I will try that.

They are suggesting that my new flapper (which is of the bulbous shape, not flat on the bottom, just needs to be worn in and, until then, the water may be escaping at exactly the rate the fill valve wants to pump it in, which is why the fill valve won't totally quiet down. She thinks it eventually will (use a small amount of vaseline, a plumbers trick) and that is my only real problem.

Well not quite: This supposedly very senior member of Kohler tech support also swears to me that the 1 B1-X fill valve should not let any water out between the very top cap and the second cap just below it (both come off when you unscrew the three screws), even though the latter has many circular holes in it. She says that is evidence of the after market part failing, even though it is brand new (and even though my other same toilet's valve lets some water out these openings and works fine). I have already unscrewed the top off twice to check for any sediment and the seating of washers and am reluctant to overtighten it, which could be the source of the water coming out near the top, assuming it's not supposed to. Can anyone address whether fresh water is supposed to come out the space between this top cap and the plastic disc right below it?

Two of the K3402 (1983, 1985) were in the house when I bought it. Both fill valves sprayed at the top (and through the holes in the back of the tank). I bought a Kohler repair kit (about $90). It sprayed from the top. I have replaced the Kohler fill valves with Fluidmaster #400A and the expensive Kohler flappers with Korky. I run plastic tubing through a rubber stopper inserted into larger tubing inserted for the rim wash. Works fine.

I have a Korky #528 fill valve in a Case kidney side handle (1926) that also works well and I would think it might serve as well as or better than the Fluidmaster #400A in the Kohler 3402.

It has occurred to me that it is possible that occasional high pressure (110psi) from hot water heating contributed to the Kohler fill valve spray. I don't have an expansion tank (yet).

Well, I am pleasantly surprised to report that, after about 10 flushes with the slight coat of vaseline on the 2-week old flapper, and after raising the water level from the too low level Kohler had been advising me to use (becasue I could see water leaking out mid hose at a junction), the unwanted siphoning action seems to have dissapeared and also very, very little water is now flowing (not spraying, fortunately) from the top cap of the fill valve now and, after a long 60 seconds or so, the toilet is now dead silent! It seems that the 4th Kohler tech may have gotten it right by mentioning the flapper. Apparently, the faster leak in the new flapper caused a pressure issue that caused more water to spray out the top of the fill valve cap and, despite that, sent the fill valve into an open loop where it would not shut off completely except at too low tank water levels which, about one minute later, casued a siphoning noise as I could see water running between the fill valve and rim wash areas. A comedy of errors with a simple, in hindsight, solution. Indeed, as you suggest, it does seem that the water flowing, even squirting out the top of the fill valve may be related to too much pressure on this finicky fill valve.

I have courageously, covered the four holes in the back of the tank, even though 2 of 4 Kohler tech advisors say that might not be a good idea! Idiot that I am, our bathrooms are carpeted, with padding no less - don't ask, so I don't want water escaping out the back of the tank (like you had)! Maybe, I'll uncover the hole on the other side from the fill valve, as a compromise.

Nevertheless, I appreciate your comments, Bob, since I (and others) was led to believe by Kohler that there were NO approved alternatives to this fill valve (and no alternatives whatsoever for the secondary float side attachment that mounts on it) and, as you may know, Kohler is still searching for a replacement manufacturer after Coast Foundries closed up shop. It sounds like, if they ever get it done, it will be a much better valve, though expensive (made in the US), but no promises as to when that will be. I think I will try the Fluidmaster unit next time around, regardless.

Any thoughts as to whether my plumber, by his 2nd unsuccessful re-visit to fix the hissing, should have suspected the flapper valve problem and interim vaseline solution?

PB in a toilet model means "plain" or round bowl, as opposed to EB elongated bowl. PB means polished brass when it is attached to trim, such as the tank lever but that is discrete from, and in addition to, the toilet designation.

I know my cap is broken. Can I get away with just getting the Cap/Plunger kit and the Plunger repair kit, instead of the whole assembly? I don't see anything else that can be broken in that assembly. The real question is, will those repair kits fit on top of the original tube? My original valve looks exactly as shown in the picture by hj. There is no lower float.

I had a Rialto that would not stop running in the five years I've owned my house. I've spent $100 on the replacement parts to stop the problem once. I've also spent money for a plumber to fix the problem. I've replaced the flapper at least twice. I've tightened and loosened the screws which worked for about a week each time. All of these were temporary fixes. About four months ago it started getting progressively worse. Finally, after a $130 water bill I replaced it with a Toto Drake this weekend. I wish I would have done that in the beginning and saved myself the headaches and the money I threw down the drain trying to fix the thing.

I got the Coast ballcock 1B1X from Lowes B&M for $9 and it seems to be working fine. It is made by PlumbPak, model number PP830-13L, Item# 246711, UPC 046224024309.

There is a very very faint hissing sound, which I can hear only with the cover off and my ear close to the tank. It stops if I just touch the float rod. Any ideas on how to stop that?

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Sounds like the plunger isn't quite shutting off.

Some basic 101:

1. Check that the overflow tube is not "overflowing"
(should fill to the line, but no further, if it's overflowing, it will keep
running, but this seems a bit unlikely, usually not quiet when it does
this)

2. Check that the flapper is seating fully
(although this usually manifests as cycling, leaking into bowl.
food color test (drops in tank, if they show up in bowl, you have
leak)

3. Turn off water, off cap (3 screws), see that plunger is free, seated
correctly. Usually if that's a problem, you will see water leak out
or spay out of the top.

Past this point, gets trickier. If you have already solved the problem, post the solution here, and if not, then we'll have another go at it.

I also have three old Kohler Rialto K-3402s. Not the best toilet made, tends to clog, but they were in the house when we bought it, and all are designer colors, matching the bathtubs, sinks, etc., so I'm inclined to keep fixing/rebuilding them, for now. (Note to self, always buy white). Don't live in an area with water supply problems, so at least I don't feel too guilty.

I did rebuild one about 5 years ago, that's been fine since, used the standard Kohler rebuild kit, wasn't easy to find, last rebuild kit at the plumbing supply or I would have bought more, but it worked, redid everything in the toilet. Now another Rialto is acting up, problem similar to some of the ones above, redid the plunger/fill valve recently, thought that would be it, but now it's cycling very slowly. Over an hour so so, loses enough water that the tank refills. Don't really hear much of anything, other than the valve is running very, very quietly, but not immediately. Tried two more Flappers, I think the seal with the flush valve is just not very good, but if I push down on them, seems to be OK for a while, but eventually cycles again. I for the life of me cannot figure out why redoing the fill valve plunger would have any impact on the flush valve/flapper side of things. Seat looks clean.